Stent with flexible hinges

Abstract

A helical stent includes at least one helical winding. Each helical winding includes a plurality of alternating long struts and short struts, ends of at least some of the long struts being joined to an end of an adjacent short strut by a flexible hinge arrangement, the struts being substantially rigid. The stent also includes at least one interconnection member connecting a hinge arrangement on one turn of the at least one winding with a hinge arrangement on an adjacent turn of the at least one winding. Fewer than all hinge arrangements on the at least one helical winding are connected to other hinge arrangements by an interconnection member.

What is claimed is: 
     
       1. An expandable stent comprising:
 a plurality of struts extending substantially longitudinally along an axis of the stent in an unexpanded configuration; and 
 a plurality of hinges interconnecting the struts, wherein the plurality of hinges each have a straight active portion which extends substantially circumferentially around the stent in the unexpanded configuration and two curved portions interconnecting the active portion to adjacent ones of the plurality of struts, wherein the straight active portion is smaller in width than the curved portions, and 
 wherein the active portions of the plurality of hinges are configured so that as the stent is expanded from the unexpanded configuration to an expanded configuration the active portions are deformed while the curved portions and the struts are substantially undeformed. 
 
     
     
       2. The stent of  claim 1 , wherein the struts include openings containing a beneficial agent, and wherein the openings are undeformed during expansion of the stent from the unexpanded configuration to an expanded configuration. 
     
     
       3. The stent of  claim 1 , wherein the plurality of struts include a plurality of short struts and a plurality of long struts positioned in an alternating arrangement, and wherein each of the plurality of hinges interconnects a short strut and a long strut. 
     
     
       4. The stent of  claim 3 , wherein the hinges have a width in the longitudinal direction of the stent and the widths of the plurality of hinges are varied to achieve uniform opening of the stent. 
     
     
       5. The stent of  claim 4 , wherein there are at least three different hinge widths located in an asymmetric pattern within the stent. 
     
     
       6. The stent of  claim 1 , wherein active portion of the plurality of hinges has a length in a circumferential direction of the stent, a width in the longitudinal direction of the stent, and a length to width ratio of 4:1 to 1:1. 
     
     
       7. The stent of  claim 6 , wherein the active portion of the plurality of hinges has a length to width ratio of about 2:1. 
     
     
       8. The stent of  claim 1 , wherein the struts have a width in a circumferential direction of the stent which is at least two times a width of the active portions of the plurality of hinges measured in the longitudinal direction of the stent. 
     
     
       9. The stent of  claim 1 , wherein the struts and hinges are interconnected to form a plurality of circumferential rings. 
     
     
       10. The stent of  claim 1 , wherein the struts and hinges are interconnected to form a plurality of helical windings. 
     
     
       11. The stent of  claim 1 , wherein the struts and hinges are interconnected to form a plurality of diamond shaped patterns. 
     
     
       12. The stent of  claim 1 , wherein the unexpanded configuration is an as-cut configuration.